Electric-arc lamp.



No. 863,568. PATBNTED AUG. 13, 1907. R'. T. FELSGH.

lT `.L'BC'I.RIG ARG LAMP. APPLIGATION FILED 11:15.21, 1901.

YOWM' fihi/v@ 1H: Ncmls PETERS ca., WASHINGTON, D. c.

REINHOLD THEODOR FELSGH, OF BOSTON, MASSACHUSETTS.

ELE CTRIC-ARC LAMP.

Specification of Letters Patent.

Patented Aug. 13, 1907.

Application filed February 21, 1907. Serial No. 358,538.

To all whom it may concern:

Be it known that l, REINHoLn Tnnonon FELsCH, a subject of Russia, residing at Boston, in the county of Suffolk and State of Massachusetts, have invented an Improvement in Electric-Arc Lamps, of which the following description7 in connection with the accompanying drawings, is a specification, like letters on the drawings representing like parts.

illy invention is an electric arc lamp, and relates particularly to means for automatically maintaining the carbons at uniform and steady arcing distance.

ln carrying oiit my invention I employ a solenoid in series with. the lamp circuit, having a split core whose opposite members are capable of moving outwardly and upwardly upon increase of current strength in the coil, said movement of the core parts or members serving to operate a clamp in engagement with the upper carbon, said clamp preferably having opposite prick points which bite into or against the opposite sides of the carbon and hold it firmly as the core moves up into the coil. As the Core members constitute in reality two separate magnets having their north poles together and their south poles together, they mutually repel each other when in a strong magnetic Iield. l provide .opposite springs for giving said core members a normal tendency to move toward each other. Hence, when the current weakens, the core members, under the influence of said springs, move slightly toward each other,

thereby loosening slightly the grip of the prick points or clamping pins against the carbon, and permit the latter to lower imperceptibly while the core members or magnets and connected clamping mechanism also move downwardly to a slight extent. As the approach of the carbons toward each other increases the liow of the current again, the increased magnetic field of the solenoid again separates forcibly the core members or magnets and raises the clamp and its carbon correspondingly.

My invention will be further explained in connection with the accompanying drawings, in which l have illustrated a preferred embodiment of my invention, and the latter will be more particularly defined in the appended claims forming a part of this specification.

In the drawings Figure 1 shows in front elevation and partly in section a lamp embodying my invention; Fig. 2 is a central vertical sectional view taken at right angles to Fig. 1. Fig. 3 is a transverse sectional view on the line 3-3, Fig. 1,

lt will be understood that in the drawings 1 have omitted showing the hood, globe, and other details of the more or less ornamental inclosure for the lamp proper, and have herein shown simply the internal mechanism of the lamp to which my invention specically relates.

Connected to a suspending hook 1 by a suitable collar or cap piece 2 is a solenoid frame or spool 3 containing usual windings 4 in series with the feed wire 5 which contains a usual resistance coil 6, and from the solenoid windings 4 passes at 7 to a post 8 or any other suitableconductor to the supporting frame 9 which carries the negative or lower carbon 10, the conductor from 7 to S being heavily insulated as indicated at l1. Depending centrally from the hollow interior 12 of the solenoid is a tube 13 slotted at one side at 14 and holding the upper or positive carbon 15 which is removably held at its upper end in a socket piece 1G from which a linger 17 projects through the slot of said tube to receive a conductor wire 18 clamped thereto by screw or binding posts 19 and secured to the tube or other fixed conductor at 20 so as to insure proper circuit conditions for the current. The tube 13 extends downwardly to a supporting plate 2l to which it is secured, where it is provided with opposite slots 22 in which operate opposite prick points or clamping pins 23 herein shown as adjustably mounted at the lower ends of opposite rods 2li. The rods 24 are pivoted at 25 in brackets 2G extending at the opposite sides of a guide sleeve 27 adapted to move up and down slightly on the tube 13. At the upper ends the rods 24 are provided with core members 2S, 29 normally held toward each other by springs 30 and connected by pins 31 operating in vertical slots 32 in said cores.

As herein shown, the supporting plate 21 not only supports the lower carbon supporting frame 9, being properly insulated therefrom, but carries on its under side a cap piece 33 to whose flange 34 is secured a glass inclosure 35 in usual manner, although l wish it understood that my lamp may be used with or without a protector. The action gives uniformity and steadiness of action, and to still further insure smoothness of movement, l secure to a bracket 3G on the tube 13 the upper member 37 of a slow motion check, herein shown as a dash pot whose piston or inner member 38 is connected by a stem 39 to the sleeve or clamp slide 27. The normal distance apart of the carbons and hence the normal amper-age of the lamp is regulated by a screw 40.

In operation, the lower carbon being in place, the upper carbon l5 is shoved into its clamping contact maker 16 and put roughly in adjustment by hand. The current is then turned on which immediately encrgizes the solenoid, the result being that the core members are immediately magnetized so that their upper ends become north and their lower ends south, which condition compels them to separate, thereby moving the clamping pins 23 in an opposite direction so that their points bite into the carbon 15 and compel the latter to move upwardly under the upward pull of the core members by reason of their position in the solenoid. As the current decreases so that the solenoid produces a weaker magnetic field, the springs 30 o the core members overcome the separating movement oi the similar' poles oi the core members and thereby move the magnets toward each other, the position, however, of the magnets being so delicately balanced by reason of their own magnetism and the action of the solenoid, that they do not let go entirely of the carbon l5, but simply shift the relative position of the parts imperceptibly.

I wish to mention particularly, as one oi the important features ot my invention7 the fact that it is extremely delicate and certain in its operation, being sensitive to the slightest variation in current and, if construeted and operated properly as set forth, practically never permitting' the upper carbon to drop, but nevertheless continually adjusting the same, so that the light remains practically constant and uniform.

As the positive carbon l slightly burns away it slowly lowers, the finger 17 sliding down the groove 14 and being permitted to `move the entire length of the tube by reason et' the flexible connection 18.

While I have herein shown one embodiment ot' my invention in its simplest form, I wish it understood that l do not intend to limit myself in all respects to the construetional details herein set lorth in this preferred l'orm ot' my invention, as the latter is capable ot various embodiments without departing lrom the spirit and scope ol' the invention.

The form ol construction herein shown is preferred because of its simplicity of mechanical details and its certainty and efciency in producing a uniform and steady arc.

Having described my invention, what I claim as new and desire to secure by Letters Patent is:

l. ln an are lamp, an automatic regulating device consisting of a solenoid responsive to the lamp current, a earbon holding tube, a slide adjacent the lower end of said tube, opposite rods pivotally carried by Said slide, springs normally holding,l said rods toward each other opposite clampingpins in the lowerends of said rods below their pivots having their points arranged to engage a carbon in said tube, and core members at the upper ends of said rods mounted in such position with relation toeach other and to the magnetic field of said solenoid as to have simi` lar poles adjacent each other.

2. In an arc lamp, an automatic regulating device consistingl of a solenoid responsive to the lamp current, a carbon holding tube, a slide adjacent the lower end ot' said tube, opposite rods pivotally carried by said slide, opposite clamping pins in the lower ends of said rods below their pivots havingr their points arranged to engage a carbon in said tube, magnetic core members at the upper ends of said rods mounted in such position with relation to each other and to the magnetic field of said solenoid as to have 'similar poles adjacent each other, and mechanical means for normally moving said core members toward each other. In testimony whereof, l have signed my name to this speciiication,- in the presence of two subscribing witnesses.

REINUOLD THEODOR FELSCH.

Witnesses z AUGUST BnnND'r, NA'rImNnL Wm'rz. 

